Drought Expands Across South, Midwest

According to the National Drought Monitor, 58.3% of the contiguous U.S. is covered by some form of drought for the week ending July 23, up from 54.39% last week but down from 80.75% from a year ago. The rise in the area covered drought came as drought conditions expanded in the South with 79.87% of the region now covered by some form of drought versus 73.47% the previous week and 82.71% a year ago. In addition, drought conditions expanded in the Midwest with 18.94% of the region covered by some form of drought versus 7.16% the previous week but well down from 85.91% a year earlier.

The week was warmer than normal and generally dry for the Midwest, the monitor reports, although storm systems brought above-normal rainfall to places, with 3 inches or more reported locally in Upper Michigan, Illinois, and southern Iowa. "Elsewhere, 5 inches or more of rain occurred with a meso-scale complex that moved through southeast Kansas and northeast Oklahoma, 5+ inches fell with storms in west Texas from the retrograding upper low, and 4+ inches were reported from storms moving through the Mid-Mississippi valley in western Tennessee and locally from monsoon rains in southern Arizona and southern New Mexico," the monitor states.

For the Midwest to Lower Mississippi Valley, "the heavy rains helped alleviate precipitation deficits in the local areas that they fell in, but they were not widespread and the deficits have been building over the last 30 to 90 days. Places unfortunate enough to have missed out on the rains had 30-day precipitation deficits of 3 inches or more," the monitor says. According to July 21 U.S. Department of Agriculture (USDA) reports, 64% of the topsoil was rated short or very short of moisture in Arkansas with 24% of the pasture and rangeland in poor or very poor condition. Missouri had 60% of the topsoil short or very short of moisture and Iowa had 57% so rated, which was a jump of 22% since last week. "Consequently, abnormally dry conditions spread eastward farther into southern Minnesota, Iowa, Missouri, Louisiana, and Mississippi," the monitor says. "Moderate drought conditions expanded in Missouri, Arkansas, Louisiana, and Mississippi; and severe drought conditions expanded in southwestern Arkansas. The rains seem to have missed southeastern Indiana, so a spot of abnormally dry was added where streamflow was below normal, soil moisture was drying out, and 90-day precipitation deficits were greatest," the monitor says.

"In the Plains, severe and moderate drought ratings were pulled back in southeast Kansas-northeast Oklahoma and southeast Oklahoma where 2+ inches of rain fell. Most of Texas had above-normal precipitation this week, so many parts of the state saw improvement. But much of the central to northern Plains was drier than normal this week," the monitor reports. "In Kansas, abnormally dry ratings expanded in the north and exceptional drought conditions in the west. A spot of abnormally dry was added to eastern North Dakota where soil moisture and 60-day precipitation deficits were driest. With 70-71% of the topsoil moisture in Nebraska and Kansas rated short or very short, 55% of the pasture and range land in Kansas in poor to very poor condition, 30-day precipitation deficits of 2-4 inches and 12-month precipitation deficits of 10 inches or more widespread across the two states, significant rains will be needed to improve conditions. Extension office reports indicated that, depending on crop emergence and crop planting times, some corn, soybean, and other crops in eastern Nebraska were burning up while others were still viable. Much of the variance was associated with rooting structures that are inadequate to meet above ground vegetative water demands. With many of the fields in the early reproductive stage, rain is especially needed in the next 7-10 days. Crops were facing a similar predicament in Missouri and Iowa," the monitor states.

The West: "Monsoon rains, enhanced by the retrograding upper low, brought above-normal precipitation to much of the Southwest, while the upper ridge inhibited showers in the Northwest and northern Rockies. Severe to moderate drought conditions were pulled back in Utah and extreme to moderate drought ratings were trimmed in Arizona. Several stations near Carlsbad reported 3.00-4.49 inches of rain, so drought ratings were pulled back in southeastern New Mexico and shaved in southwestern New Mexico. Over 6 inches of moisture has fallen in July to date over parts of south central Colorado where extreme drought was trimmed, recent rains improved crop conditions resulting in pullback of drought ratings in northeastern Colorado, and moderate drought rating shrank near Denver and other Front Range communities due to improving vegetation and reservoir levels. But the drought is far from over in the Southwest, with 80% of the topsoil short or very short of moisture in Colorado and New Mexico, 74% so rated in Oregon, and over 60% that dry in Utah. As of July 21, the USDA reported pasture and range land in poor to very poor condition for 95% of California, 79% of Arizona and New Mexico, 70% of Nevada, and 64% of Colorado," the monitor reports.

"Drier and warmer than normal weather further dried out soils in the northern states of the West," reports the monitor, "with the USDA rating topsoil short or very short of moisture for 62% of Wyoming and 47% of Montana, which are jumps of 14% and 10%, respectively, from last week. The Palmer Crop Moisture Index showed progressively worsening conditions. This week began with only 4 large wildfires burning in the Northwest, but it ended with firefighters battling over a dozen. As a result, abnormally dry and moderate drought conditions expanded in northern Idaho and western Montana, and extreme drought expanded into southwestern Wyoming," says the monitor.

"Long-term conditions remained wet across the East," reports the monitor. "While locally heavy rains occurred in a few places, above-normal temperatures and generally below-normal precipitation this week continued a drying trend for the Northeast. Although soil moisture continued to decrease, little negative impact was felt by agricultural interests so no change was made to the drought monitor map, although the Northeast region should be watched if the heat and dryness continue. The Southeast averaged cooler than normal with areas of above- and below-normal rainfall. The eastern half of North Carolina was dry, but there were no signs of drought or negative impacts statewide," the monitor says.